Continuous battery charger system

ABSTRACT

A battery charger system, for use with an injector system, comprises a power supply and a battery pack. The power supply converts AC power to DC power. The battery pack includes a battery and a charging module. The module monitors the operating mode of the injector system. When the battery pack is disconnected from the injection control unit, the module enables the power supply to charge the battery with DC power. When the battery pack is connected to the injection control unit: (A) upon detecting the injector system in an idle mode, the module routes DC power from the power supply to both the battery for charging thereof and the injection control unit for operation thereof; and (B) upon detecting the injector system in a non-idle mode, the module prevents the power supply from charging the battery and enables the battery to provide DC power to the injection control unit.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application for patent claims the benefit of U.S. ProvisionalApplication Ser. No. 60/429,511 titled Continuous Battery ChargerSystem, filed Nov. 27, 2002. This provisional application has beenassigned to the assignee of the invention disclosed below, and itsteachings are incorporated into this document by reference.

FIELD OF THE INVENTION

The invention relates generally to injector systems of the type usedwith magnetic resonance imaging (MRI) systems to inject contrast mediainto a patient to enhance the quality of images obtainable during scansof the organs and other internal structures. More particularly, theinvention relates to systems and methods of powering such injectorsystems. Even more particularly, the invention pertains to a continuousbattery charger system capable not only of allowing the battery for aninjection control unit of such an injector system to power the injectioncontrol unit while it is functioning in a non-idle mode of operation butalso of charging the battery of such an injection control unit andpowering its operations while the injection control unit is functioningin an idle mode of operation.

BACKGROUND OF THE INVENTION

The following information describes one of the many possibleenvironments in which the invention can be used. It is provided toassist the reader to understand the invention, as novel material isoften more readily understood if described in a familiar context.

Magnetic resonance imaging (MRI) is a noninvasive method of producinghigh quality images of the interior of the human body. It allows medicalpersonnel to see inside the body (e.g., organs, muscles, nerves, bones,and other structures) without surgery or the use of potentially harmfulionizing radiation such as X-rays. The images are of such highresolution that disease and other forms of pathology can often bevisually distinguished from healthy tissue. Magnetic resonance (MR)systems and techniques have also been developed for performingspectroscopic analyses by which the chemical content of tissue or othermaterial can be ascertained.

MR imaging and spectroscopic procedures are performed in what is knownas an MR suite. As shown in FIG. 1A, an MR suite typically has threerooms: a scanner room 1, a control room 2, and an equipment room 3. Thescanner room 1 houses the MR scanner 10 into which a patient is movedvia a slideable table 11 to undergo a scanning procedure, and thecontrol room 2 contains a computer console 20 from which the operatorcontrols the overall operation of the MR system. In addition to a door4, a window 5 is typically set in the wall separating the scanner andcontrol rooms to allow the operator to observe the patient during suchprocedures. The equipment room 3 contains the various subsystemsnecessary to operate the MR system. The equipment includes a powergradient controller 31, a radio frequency (RF) assembly 32, aspectrometer 33, and a cooling subsystem 34 with which to avoid thebuild up of heat which, if left unaddressed, could otherwise interferewith the overall performance of the MR system. These subsystems aretypically housed in separate cabinets, and are supplied electricitythrough a power distribution panel 12 as are the scanner 10 and theslideable patient table 11.

An MR system obtains such detailed images and spectroscopic results bytaking advantage of a basic property of the hydrogen atom, which isfound in abundance in all cells within the body. Within the body'scells, the nuclei of hydrogen atoms naturally spin like a top, orprecess, randomly in every direction. When subject to a strong magneticfield, however, the spin-axes of the hydrogen nuclei align themselves inthe direction of that field. This is because the nucleus of the hydrogenatom has what is referred to as a large magnetic moment, which isbasically an inherent tendency to line up with the direction of themagnetic field to which it is exposed. During an MR scan, the entirebody or even just one region thereof is exposed to such a magneticfield. This causes the hydrogen nuclei of the exposed region(s) to lineup—and collectively form an average vector of magnetization—in thedirection of that magnetic field.

As shown in FIGS. 1B and 1C, the scanner 10 is comprised of a mainmagnet 101, three gradient coils 103a-c, and, usually, an RF antenna 104(often referred to as the whole body coil). Superconducting in nature,the main magnet 101 is typically cylindrical in shape. Within itscylindrical bore, the main magnet 101 generates a strong magnetic field,often referred to as the B₀ or main magnetic field, which is bothuniform and static (non-varying). For a scanning procedure to beperformed, the patient must be moved into this cylindrical bore,typically while supine on table 11, as best shown in FIGS. 1B and 1C.The main magnetic field is oriented along the longitudinal axis of thebore, referred to as the z direction, which compels the magnetizationvectors of the hydrogen nuclei in the body to align themselves in thatdirection. In this alignment, the hydrogen nuclei are prepared toreceive RF energy of the appropriate frequency from RF coil 104. Thisfrequency is known as the Larmor frequency and is governed by theequation ω=YB₀, where ω is the Larmor frequency (at which the hydrogenatoms precess), Y is the gyromagnetic constant, and B₀ is the strengthof the main magnetic field.

The RF coil 104 is generally used both to transmit pulses of RF energyand to receive the resulting magnetic resonance (MR) signals inducedthereby in the hydrogen nuclei. Specifically, during its transmit cycle,the coil 104 broadcasts RF energy into the cylindrical bore. This RFenergy creates a radio frequency magnetic field, also known as the RF B₁field, whose magnetic field lines point in a direction perpendicular tothe magnetization vectors of the hydrogen nuclei. The RF pulse (or B₁field) causes the spin-axes of the hydrogen nuclei to tilt with respectto the main (B₀) magnetic field, thus causing the net magnetizationvectors to deviate from the z direction by a certain angle. The RFpulse, however, will affect only those hydrogen nuclei that areprecessing about their axes at the frequency of the RF pulse. In otherwords, only the nuclei that “resonate” at that frequency will beaffected, and such resonance is achieved in conjunction with theoperation of the three gradient coils 103a-c.

Each of the three gradient coils is used to vary the main (B₀) magneticfield linearly along only one of the three spatial directions (x,y,z)within the cylindrical bore. Positioned inside the main magnet as shownin FIG. 1C, the gradient coils 103a-c are able to alter the mainmagnetic field on a very local level when they are turned on and offvery rapidly in a specific manner. Thus, in conjunction with the mainmagnet 101, the gradient coils can be operated according to variousimaging techniques so that the hydrogen nuclei—at any given point or inany given strip, slice or unit of volume—will be able to achieveresonance when an RF pulse of the appropriate frequency is applied. Inresponse to the RF pulse, the precessing hydrogen nuclei in the selectedregion absorb the RF energy being transmitted from RF coil 104, thusforcing the magnetization vectors thereof to tilt away from thedirection of the main (B₀) magnetic field. When the RF coil 104 isturned off, the hydrogen nuclei begin to release the RF energy they justabsorbed in the form of magnetic resonance (MR) signals, as explainedfurther below.

One well known technique that can be used to obtain images is referredto as the spin echo imaging technique. Operating according to thistechnique, the MR system first activates one gradient coil 103a to setup a magnetic field gradient along the z-axis. This is called the “sliceselect gradient,” and it is set up when the RF pulse is applied and isshut off when the RF pulse is turned off. It allows resonance to occuronly within those hydrogen nuclei located within a slice of the regionbeing imaged. No resonance will occur in any tissue located on eitherside of the plane of interest. Immediately after the RF pulse ceases,all of the nuclei in the activated slice are “in phase,” i.e., theirmagnetization vectors all point in the same direction. Left to their owndevices, the net magnetization vectors of all the hydrogen nuclei in theslice would relax, thus realigning with the z direction. Instead,however, the second gradient coil 103b is briefly activated to create amagnetic field gradient along the y-axis. This is called the “phaseencoding gradient.” It causes the magnetization vectors of the nucleiwithin the slice to point, as one moves between the weakest andstrongest ends of this gradient, in increasingly different directions.Next, after the RF pulse, slice select gradient and phase encodinggradient have been turned off, the third gradient coil 103c is brieflyactivated to create a gradient along the x-axis. This is called the“frequency encoding gradient” or “read out gradient,” as it is onlyapplied when the MR signal is ultimately measured. It causes therelaxing magnetization vectors to be differentially re-excited, so thatthe nuclei near the low end of that gradient begin to precess at afaster rate, and those at the high end pick up even more speed. Whenthese nuclei relax again, the fastest ones (those which were at the highend of the gradient) will emit the highest frequency of radio waves andthe slowest ones emit the lowest frequencies.

The gradient coils 103a-c therefore allow these radio waves to bespatially encoded, so that each portion of the region being imaged isuniquely defined by the frequency and phase of its resonance signal. Inparticular, as the hydrogen nuclei relax, each becomes a miniature radiotransmitter, giving out a characteristic pulse that changes over time,depending on the local microenvironment in which it resides. Forexample, hydrogen nuclei in fats have a different microenvironment thando those in water, and thus emit different pulses. Due to thesedifferences, in conjunction with the different water-to-fat ratios ofdifferent tissues, different tissues emit radio signals of differentfrequencies. During its receive cycle, RF coil 104 detects theseminiature radio emissions, which are often collectively referred to asthe MR signal(s). From the RF coil 104, these unique resonance signalsare conveyed to the receivers of the MR system where they are convertedinto mathematical data. The entire procedure must be repeated multipletimes to form an image with a good signal-to-noise ratio (SNR). Usingmultidimensional Fourier transformations, the MR system then convertsthe mathematical data into a two- or even a three-dimensional image ofthe body, or region thereof, that was scanned.

As shown partially in FIG. 1A, the scanner room 1 is shielded to preventthe entry and exit of electromagnetic waves. Specifically, the materialsand design of its ceiling, floor, walls, door, and window effectivelyform a barrier or shield 6 that prevents the electromagnetic signalsgenerated during a scanning procedure (e.g., the RF energy) from leakingout of scanner room 1. Likewise, shield 6 is designed to preventexternal electromagnetic noise from leaking into the scanner room 1. Theshield 6 is typically composed of a copper sheet material or some othersuitable conductive layer. The window 5, however, is typically formed bysandwiching a wire mesh material between sheets of glass or by coatingthe window with a thin layer of conductive material to maintain thecontinuity of the shield. The conductive layer also extends to the door4, which when open allows access to the scanner room 1 and yet whenclosed is grounded to and constitutes a part of shield 6. The ceiling,floor, walls and door of shield 6 provide approximately 100 decibels(dB) of attenuation, and window 5 approximately 80 dB, for the typicaloperating range of MR scanners (˜20 to 200 MHz). Barrier 6 thus shieldsthe critical components (e.g., scanner, preamplifiers, receivers, localcoils, etc.) of the MR system from undesirable sources ofelectromagnetic radiation (e.g., radio signals, television signals, andother electromagnetic noise present in the local environment).

The shield 6 serves to prevent external electromagnetic noise frominterfering with the operation of the scanner 10, which if not addressedcould otherwise result in degradation of the images and/or spectroscopicresults obtained during the scanning procedures. For the scanner 10 tooperate, however, the shield 6 must still allow communication of dataand control signals between the scanner room 1 and the control andequipment rooms 2 and 3, and such communication is generallyaccomplished through a penetration panel 16.

As shown in FIG. 1A, the penetration panel 16 is typically incorporatedinto the wall between the scanner and equipment rooms 1 and 3. Itfeatures several ports through which the scanner 10 and other devices inthe scanner room 1 are connected by cables to the computer console 20and control subsystems in the control and equipment rooms 2 and 3,respectively. Each port typically includes a filtered BNC connector,which allows the communication of data and/or control signals whilestill maintaining the barrier to unwanted electromagnetic signals.

Several auxiliary systems designed for use in the MR suite requirecommunication across the shield 6. These systems are typicallybifurcated, i.e., they have two pieces of equipment, with one piecelocated in the scanner room 1 and the other situated in the control room2. One example is the Spectris® MR Injector System produced by Medrad,Inc., of Indianola, Pa. It allows contrast media to be injected into theblood stream of a patient undergoing an MR procedure. (As is well known,contrast media serves to increase the contrast between the differenttypes of tissues in the region of the body undergoing a scan, andthereby enhances the resolution of the images obtained during the scan.)In this bifurcated system, an injection control unit in the scanner room1 with which to inject the contrast media into the patient requirescommunication with a controller therefor situated in the control room 2.This is disclosed in U.S. Pat. No. 5,494,036 to Uber, III et al.,incorporated herein by reference. The '036 patent discloses that theinjection control unit and its controller communicate across shield 6using a pair of transceivers attached to, and aimed at each otherthrough, opposite sides of window 5. They allow the injection controlunit and controller to communicate, via the transceivers and theirassociated fiber optic cables, at frequencies (e.g., infrared or visual)that readily penetrate the shield 6 yet do not adversely affect theoperation of the MR system.

The Spectris® Solaris™ MR Injector System, which is also produced byMedrad, Inc., uses a fiber optic link only, without resort totransceivers, to convey its data and control signals across the barrier6. As shown in FIG. 2, this injector system has its fiber optic cable 13routed through the shield 6 (i.e., preferably through one of the tunedports in penetration panel 16) to enable optical communication betweenits injection control unit 50 and its controller 60. Because thecommunications links of the aforementioned injector systems areimplemented optically, they do not introduce any potentially troublesomeRF interference into the scanner room 1 as would be the case if standardwire cabling were used.

More relevant to the invention disclosed below, several prior artinjector systems use batteries to supply power to their injectioncontrol units rather than AC power. One disadvantage of running AC powercords in the scanner room 1, particularly if close to the scanner 10, isthat unless heavily shielded they tend to radiate RF emissions, whichcan interfere with the operation of the scanner 10 and cause artifactsto appear in the resulting images. The Spectris® Solaris™ MR InjectorSystem, for example, as shown in FIG. 2, has its injection control unit50 powered with a battery pack 40 that plugs into a corresponding socket52 within the lower console housing 51. The battery pack 40 isrechargeable through use of a separate battery charger 41, as shown inFIG. 3.

Although it reduces the likelihood of tripping accidents due to theabsence of power cords in the scanner room 1, the use of a stand-alonebattery pack still poses several disadvantages to the operators ofinjector systems so equipped. First, the operator must regularly monitorthe state of charge of the battery packs, which can generally be done inconjunction with most injector systems. If a battery pack with a lowstate of charge is not detected in a timely fashion, however, thescanning procedure will have to be delayed while the depleted batterypack in the injection control unit is swapped for a fully-charged onefrom the battery charger. At hospitals and other sites that routinelyperform high numbers of contrast-enhanced procedures, such delays areparticularly burdensome, as the battery packs must be swapped relativelyoften. Such delays inevitably reduce the number of patients that can bescanned in any given time period. This not only decreases the amount ofrevenue that can be derived from the MR suite but also ultimatelyimposes greater overall costs on the providers, and hence users, ofmedical services.

The Optistar™ Injector System, produced by the Liebel-Flarsheim Companyof Mallinckrodt Inc., a division of Tyco International Ltd., attempts toovercome these disadvantages by routing DC power from the control orequipment rooms 2 and 3 through penetration panel 16 into the scannerroom 1. As disclosed in U.S. Patent Application Publication No.2002/0169415, situated in the control room is a power supply, which hasan off-the-shelf AC/DC converter and a standard data link incorporatedinto one box. At its input, the AC/DC converter plugs into either a 115vAC outlet or a 240v AC outlet. An RF shielded cable from the powersupply box routes power conductors (which carry DC power from the outputof the AC/DC converter) and data conductors (which carry data andcontrol signals to and from the computer console) through thepenetration panel into the scanner room. The power conductors areconnected directly to existing wiring within the battery compartment ofthe injection control unit, thereby eliminating the need for batterieswhich were necessary to operate an earlier pre-power supply version ofthe Optistar™ Injector System. In the Optistar™ Service and Parts Manual801993-A (April 2001) with amended Installation Instructions 801995-A(May 2001), the power supply box is shown deployed in either the controlroom or the equipment room.

The advantage of such a power supply scheme is that heavy users of suchinjector systems do not have to contend with the task of swappingbatteries. Although this scheme provides an uninterrupted supply of DCpower to the injection control unit, it denies the user the increasedmobility that an injection control unit has in the scanner room whenpowered by batteries. This shortcoming is but one of several that theLiebel-Flarsheim power supply scheme exhibits when compared to theinvention disclosed below. The advantages of the invention hereinpresented will become fully apparent to persons skilled in the relevantart from a reading of the detailed description section of this document,and will become particularly apparent when the detailed description isconsidered along with the drawings and claims presented herein.

SUMMARY OF THE INVENTION

The objectives and advantages of the invention are attained by thevarious embodiments and related aspects of the invention summarizedbelow.

In a presently preferred embodiment, the invention provides a batterycharger system for an injector system that has an idle mode of operationand a non-idle mode of operation. The battery charger system comprises afirst power cord, an AC/DC converter, a second power cord, and a batterypack. The first power cord is for conveying AC power from a sourcethereof. The AC/DC converter is used to convert the AC power receivedfrom the first power cord to DC power. The second power cord is used toconvey the DC power received from an output of the AC/DC converter. Thebattery pack includes a battery and a charging module. The chargingmodule is for receiving the DC power from the AC/DC converter via thesecond power cord and for monitoring the operating mode of the injectorsystem. When the injector system is operating in the idle mode, thecharger module provides DC power received from the AC/DC converter tothe battery for the charging thereof. When the injector system isoperating in the non-idle mode, the charger module prevents DC powerfrom the AC/DC converter from reaching the battery and thus enables thebattery to provide DC power to the injector system.

In a related aspect, the charger module also provides DC power receivedfrom the AC/DC converter to the injector system when the injector systemis operating is the idle mode.

In a related embodiment, the invention also provides a battery chargersystem for use with an injection control unit of an injector system. Thebattery charger system comprises an AC/DC converter and a battery pack.The AC/DC converter is used to convert AC power from a source thereof toDC power. The battery pack includes a battery and a charging module. Thecharging module is for monitoring an operating mode of the injectorsystem. When the battery pack is disconnected from the injection controlunit, the charging module enables the AC/DC converter to charge thebattery with the DC power therefrom. When the battery pack is connectedto the injection control unit: (A) upon detecting the injector system inan idle mode of operation, the charger module routes the DC power fromthe AC/DC converter to both the battery for the charging thereof and theinjection control unit for operation thereof; and (B) upon detecting theinjector system in a non-idle mode of operation, the charger moduleprevents the AC/DC converter from charging the battery and enables thebattery to provide DC power to the injection control unit.

In a related aspect, the invention also provides a charging module for abattery for use with an injection control unit of an injector system.The charging module comprises an output selector stage, a chargingstage, and an indicator stage. The output selector stage is for sensingthe mode of operation of the injection control unit and for providing aturn-on signal when the injection control unit is operating in an idlemode and a turn-off signal when the injection control unit is operatingin a non-idle mode. The charging stage is connected to the outputselector stage. Upon receiving the turn-off signal, the charging stageprevents the battery from being charged by a power supply therefor andenables the battery to provide DC power to the injection control unit.Upon receiving the turn-on signal, the charging stage enables DC powerfrom the power supply to be conveyed to the injection control unit andassumes either a low current charging mode or a multi-state chargingmode. When a voltage level of the battery is less than a preselectedminimum level, the charging stage assumes the low current charging modewherein the charging stage charges the battery with a charging currentlimited to a trickle level. When the voltage level of the battery is thepreselected minimum level or greater, the charging stage assumes themulti-state charging mode wherein the charging stage operates accordingto (I) a bulk-charge state, when the voltage level of the battery is thepreselected minimum level or greater yet below a set percentage of anovercharge level, wherein the charging stage charges the battery with acharging current at a peak level thereof; (II) an over-charge state,when the voltage level of the battery is equal to or exceeds the setpercentage of the overcharge level, wherein the charging stage continuescharging the battery until the charging current falls to a minimumthreshold; and (III) a standby state, when the charging current fallsbelow the minimum threshold, wherein the charging stage applies aconstant voltage to the battery until the voltage level of the batterydrops at least a specified percentage below a float level upon which thecharging stage will commence operating according to the bulk-chargestate. The indicator stage is for indicating when the power supply iscapable of providing to the charging module sufficient power toefficiently charge the battery.

The invention also provides an injector system comprising an injectioncontrol unit, a controller, and a battery charger system. The injectioncontrol unit is for use in injecting a medicinal substance into apatient. The controller is for controlling the operation of the injectorsystem inclusive of whether the injector system operates in an idle modeof operation or a non-idle mode of operation. The battery charger systemis for providing power to the injection control unit. The batterycharger system comprises a power supply and a battery pack. The powersupply is for converting AC power from a source thereof to DC power. Thebattery pack includes a battery and a charging module. The chargingmodule is for monitoring the mode of operation of the injector system.When the battery pack is disconnected from the injection control unit,the charging module enables the power supply to charge the battery withthe DC power therefrom. When the battery pack is connected to theinjection control unit: (A) upon detecting the injector system in theidle mode, the charger module routes the DC power from the power supplyto both the battery for the charging thereof and the injection controlunit for operation thereof; and (B) upon detecting the injector systemin the non-idle mode, the charger module prevents the power supply fromcharging the battery and enables the battery to provide DC power to theinjection control unit.

The invention further provides a battery charger system for use with abattery-powered system. The battery charger system comprises a powersupply and a battery pack. The power supply is for supplying DC power.The battery pack includes a battery and a charging module. The chargingmodule is connectible to the power supply for receiving the DC powertherefrom and is capable of monitoring an operating mode of thebattery-powered system when linked thereto. When the battery pack isdisconnected from the battery-powered system, the charging moduleenables the power supply to charge the battery with the DC powertherefrom. When the battery pack is connected to the battery-poweredsystem: (A) upon detecting the battery-powered system in an idle mode ofoperation, the charger module routes the DC power from the power supplyto both the battery for the charging thereof and the battery-poweredsystem for operation thereof; and (B) upon detecting the battery-poweredsystem in a non-idle mode of operation, the charger module prevents thepower supply from charging the battery and enables the battery toprovide DC power to the battery-powered system.

In a related aspect, the invention also provides a charging module for abattery for use with a battery-powered system. The charging modulecomprises an output selector stage and a charging stage. The outputselector stage is for sensing the current drawn by the battery-poweredsystem and for providing a turn-on signal when the current is less thana predetermined level and a turn-off signal when the current is greaterthan the predetermined level. The charging stage is connected to theoutput selector stage. Upon receiving the turn-off signal, the chargingstage prevents the battery from being charged by a power supply thereforand enables the battery to provide DC power to the battery-poweredsystem. Upon receiving the turn-on signal, the charging stage enables DCpower from the power supply to be conveyed to the battery-powered systemand assumes either a low current charging mode or a multi-state chargingmode. When a voltage level of the battery is less than a preselectedminimum level, the charging stage assumes the low current charging modewherein the charging stage charges the battery with a charging currentlimited to a trickle level. When the voltage level of the battery is thepreselected minimum level or greater, the charging stage assumes themulti-state charging mode wherein the charging stage operates accordingto (I) a bulk-charge state, when the voltage level of the battery is thepreselected minimum level or greater yet below a set percentage of anovercharge level, wherein the charging stage charges the battery with acharging current at a peak level thereof; (II) an over-charge state,when the voltage level of the battery is equal to or exceeds the setpercentage of the overcharge level, wherein the charging stage continuescharging the battery until the charging current falls to a minimumthreshold; and (III) a standby state, when the charging current fallsbelow the minimum threshold, wherein the charging stage applies aconstant voltage to the battery until the voltage level of the batterydrops at least a specified percentage below a float level upon which thecharging stage will commence operating according to the bulk-chargestate.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, and particularly its presently preferred and alternativeembodiments and related aspects, will be better understood by referenceto the detailed disclosure below and to the accompanying drawings, inwhich:

FIG. 1A illustrates the layout of an MR suite inclusive of the scannerroom in which the scanner and patient table are located, the controlroom in which the computer console for controlling the scanner issituated, and the equipment room in which various control subsystems forthe scanner are sited.

FIG. 1B shows a scanner and patient table of the type shownschematically in FIG. 1A.

FIG. 1C is a more detailed view of the MR system shown in FIGS. 1A and1B showing the computer console and the various subsystems located inthe control and equipment rooms and a cross-section of the scanner andpatient table situated in the scanner room.

FIG. 2 illustrates a prior art MR injector system showing (i) itsinjection control unit in the scanner room and its controller in thecontrol room linked via the penetration panel through which theycommunicate and (ii) a prior art battery pack that plugs into acorresponding socket within the injection control unit by which it issupplied with DC power.

FIG. 3 illustrates a battery charger for the prior art battery pack ofFIG. 2.

FIG. 4 illustrates a preferred embodiment of the invention, showing apower supply and an AC power cord therefor, a battery pack, and a DCpower cord interconnecting them.

FIG. 5A is an exploded view of the battery pack depicted in FIG. 4,showing the upper and lower halves of its case and the batteries andcharging module enclosed therein.

FIG. 5B is a perspective view of the battery pack of FIG. 5A in itsfully assembled state.

FIG. 5C is a perspective view of the battery pack of FIG. 5A from itsopposite end.

FIG. 6A is a schematic circuit diagram of the charging module accordingto the preferred embodiment of the invention.

FIG. 6B is a schematic circuit diagram of the charging module accordingto another embodiment of the invention.

FIG. 7 is a graph showing the charging modes of the charging moduleaccording to the preferred embodiment of the invention.

FIG. 8A illustrates a first configuration for the invention wherein thepower supply and AC power cord are situated in the control room of theMR suite, and the DC power cord is routed through the penetration panelseparating the control and scanner rooms and is connected to the batterypack of the invention in the scanner room.

FIG. 8B shows a preferred manifestation of the DC power cord of FIG. 8A.

FIG. 8C illustrates one way of routing the DC power cord of FIG. 8Bthrough the penetration panel.

FIG. 8D illustrates another way of routing the DC power cord of FIG. 8Bthrough the penetration panel.

FIG. 9 illustrates a second configuration for the invention wherein thepower supply, the battery pack, and the DC power cord interconnectingthem are all situated within the scanner room of the MR suite, with theAC power cord from the power supply plugged into an AC outlet in thescanner room.

FIG. 10 illustrates a block diagram of the invention as used with aninjector control unit.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED AND ALTERNATIVEEMBODIMENTS OF THE INVENTION

Although the invention herein described and illustrated is presented inthe context of injector systems designed for use in the MR environment,the reader will understand that the invention can be applied or adaptednot only to a wide variety of other systems but also to various othertypes of environments. The presently preferred embodiment and relatedaspects of the invention will now be described with reference to theaccompanying drawings, in which like elements have been designated wherepossible by the same reference numerals.

FIGS. 4-6B illustrate the invention, namely, a continuous batterycharger (CBC) system, generally designated 100. The CBC system 100includes an AC power cord 110, a power supply 120, a DC power cord 130,and a battery pack 140. The CBC system 100 is described below in thecontext of an injection control unit 50 for the Spectris® Solaris™injector system, although it is equally applicable to other systems andenvironments as noted above.

The power supply 120 may take the form of an AC/DC converter such as theGLM65-15 medical grade switcher manufactured by Condor Power Supplies,Inc., of Oxnard, Calif. As disclosed in Condor Publication No.41-34796-0001 Rev. E (Jul. 30, 2002) and the data sheet(s) correspondingthereto, incorporated herein by reference, the GLM65-15 power supply iscapable of providing 65 Watts (W) at 15 Volts (V) DC from an input of90-264V AC. Although the CBC system 100 in its preferred embodimentrequires approximately only 20.96 W when used with the Spectris®Solaris™ injector system, the GLM65-15 was chosen at least partlybecause of its use in other injector systems produced by Medrad, Inc.Those skilled in the design and development of injector systems andassociated circuitry realize, of course, that the particular powersupply chosen need only meet the power requirements of the specificinjector system with which it is used. The GLM65-15 power supply alsoprovides the CBC system 100 with protection against short circuits andoverloading at its output. FIG. 4 shows the AC and DC power cords 110and 130 connected to opposite ends of power supply 120.

As best shown in FIG. 5A, the battery pack 140 includes at least onebattery 143 and a charging module 400. For the preferred application ofinjection control unit 50, the battery pack preferably includes twoModel BP5-6 lead-acid batteries produced by the B.B. Battery Co., Ltd.The two BP5-6 batteries are shown connected in series to charging module400. The batteries 143 and charging module 400 are contained within asingle case comprised of first and second halves 141 and 142. As shownin FIG. 5B, the DC power cord 130 preferably connects to the chargingmodule through the handle 144 of battery pack 140. FIG. 5C shows theother end of the battery pack 140 at which the output terminals 145 ofthe battery pack are situated. When the battery pack 140 is plugged intothe socket 52 of console 51 of injection control unit 50, the outputterminals 145 contact the corresponding battery contacts within theinjection control unit 50 to provide DC power thereto. FIG. 5C alsoshows an indicator light 487 with which to signify the operational stateof the invention.

When the battery pack 140 is plugged into injection control unit 50, thecharging module 400 allows the power supply 120 not only to charge thebatteries 143 but also to provide power to the injection control unitwhile it is functioning in its standby or idle mode of operation. Thecharging module 400 does not, however, allow DC power from power supply120 to power the injection control unit while it is operating in itsnon-idle mode of operation. When operating in its non-idle mode, theinjection control unit 50 gets its power only from the batteries 143.Conversely, when battery pack 140 is unplugged from injection controlunit 50, the charging module 400 still allows power supply 120 to chargethe batteries 143. Furthermore, when power supply 120 is disconnectedfrom battery pack 140, the charging module 400 enables the batteries toprovide power to injection control unit 50 regardless of its mode ofoperation.

The charging module 400 includes an output selector stage 410, acharging stage 440, an indicator stage 480, and a regulator stage 490,all of which described herein in the context of its presently preferredembodiment shown in FIG. 6A. An alternative embodiment of the chargermodule 400 is illustrated in FIG. 6B.

The regulator stage 490 may be implemented using any one of a variety ofregulator circuits known in the electrical/electronic arts. Theregulator illustrated in FIG. 6A, for example, is a precision voltagereference produced and sold under Model No. REF02 by Analog Devices,Inc., of Norwood, Mass. As disclosed in Rev. C (2002) of itsspecification sheet, incorporated herein by reference, the REF02regulator 490 is capable of providing a stable 5V DC output, regulatedto approximately ±1%, from the 15V DC input received from the GLM65-15power supply 120 via DC power cord 130. This 5V DC reference voltage issupplied to both the output selector stage 410 and the indicator stage480.

The output selector stage 410 includes a current monitoring circuit 420,a comparator circuit 425, and one or more Schottky Barrier rectifyingdiodes 430. The current monitoring circuit 420 can take the form of acurrent shunt monitor 421 such as the INA138 chip made by TexasInstruments Inc., as disclosed in Datasheet SBOS122A (Rev. 12-2002),incorporated herein by reference. The comparator circuit 425 can beimplemented with the LM2903MX differential comparator chip produced byFairchild Semiconductor Corporation. As shown in FIG. 6A, both chips arepowered with 15V DC received from the GLM65-15 power supply 120.

The current shunt monitor 421 has its V_(IN−) input connected to theexternal load, which in this preferred application is injection controlunit 50. Resistors R₆ and R₇, acting as current sampling resistors, areconnected in parallel across inputs V_(IN+) and V_(IN−). The output ofchip 421 is connected to an external load resistor R₁₂. Differentialcomparator 425 has its positive input connected to the output or OUTterminal of current shunt monitor 421 and its negative input connectedto the regulator 490 through a resistor divider network, R₁₃ and R₁₆.The Schottky Barrier diodes 430 are connected in parallel between theV_(IN+) input of current monitor chip 421 and the positive (V_(Batt))terminal of batteries 143.

The resistors R₆ and R₇ are used by chip 421 to monitor the currentdrawn by injection control unit 50, whether it is drawn from thebatteries 143 (V_(Batt)) via the Schottky Barrier diodes 430 or from thepower supply 120 via transistor 470, series diode 471 and Schottky diode472. The differential input voltage that the current shunt monitor 421detects at its inputs V_(IN+) and V_(IN−), via resistors R₆ and R₇, isconverted to an interim current and delivered to the OUT terminal ofchip 421. This current is then converted back to a voltage by externalload resistor R₁₂ at the OUT terminal. For the preferred application ofinjection control unit 50, sampling resistors R₆ and R₇ and loadresistor R₁₂ are preferably selected so that the current flowing toinjection control unit 50 if less than 680 mA yields a correspondingoutput voltage of less than 0.68V and if greater than 680 mA yields acorresponding output voltage of greater than 0.68V (i.e., 1A≈1V). The680 mA level was chosen because when injection control unit 50 drawsless it is functioning in its idle or standby mode of operation.Conversely, when it draws more than that predetermined level, theinjection control unit is functioning in its non-idle mode of operation.

The resistor divider network of comparator circuit 425 steps down the 5VDC received from regulator 490 to a nominal reference voltage. For thepreferred application of injection control unit 50, resistors R₁₃ andR₁₆ are selected so that a reference voltage of 0.68V exists at thenegative terminal of the comparator chip 425. The output of thecomparator chip thus depends on the voltage output by the currentmonitor chip 421 at its OUT terminal. When the output voltage at itspositive input is less than 0.68V, the comparator chip 425 outputs a lowlevel logic signal (i.e., turn-on signal). This signal signifies thatinjection control unit 50 is drawing less than 680 mA, and thusfunctioning in the idle mode of operation. Conversely, when the outputvoltage at its positive input is greater than 0.68V, the comparator chipoutputs a high level logic signal (i.e., turn-off signal). This turn-offsignal indicates that injection control unit 50 is drawing more than 680mA, and thus functioning in the non-idle mode of operation.

The charging stage 440 features a charging circuit 450 and theactivating transistor 470. The charging circuit 450 includes a batterycharger controller 451, a pass transistor 455, a sense resistor R₃, aresistor divider network 460, and a Schottky diode 469. The batterycharger controller 451 is preferably implemented as the Unitrode UC3906controller chip produced by Texas Instruments Inc. and disclosed inDatasheet SLUS186B (Rev. July 2003), incorporated herein by reference.The activating transistor 470 is preferably the SFW/I9Z24 P-channelMOSFET made by Fairchild Semiconductor Corporation, and pass transistor455 can take the form of a PNP transistor such as the KSE45H11 powertransistor made by ST Microelectronics.

The activating transistor 470 is connected by its source to the 15V DCpower supply 120 from which the charging circuit 450 receives its power.By its drain, transistor 470 connects to the +V_(IN) and CURRENT SENSE+terminals of chip 451 and, through sense resistor R₃, to the emitter orinput of pass transistor 455. The collector or output of pass transistor455 connects, via Schottky diode 469, to the V_(Batt) terminal ofbatteries 143 and to the anodes of Schottky Barrier diodes 430. Thedrain of transistor 470 is also connected, via series diode 471 andSchottky diode 472, to the cathodes of Schottky Barrier diodes 430 andthe V_(IN+) input of current shunt monitor 421 as well as to samplingresistors R₆ and R₇. The sense resistor R₃ is connected across the+V_(IN) and CURRENT SENSE+ terminals and the CURRENT LIMIT and CURRENTSENSE− terminals of chip 451. Resistors R₄, R₈, R₉ and R₁₀ of resistordivider network 460 are variously connected to the VOLTAGE SENSE, CHARGEENABLE, STATE LEVEL CONTROL and POWER INDICATE terminals of chip 451.Resistor R₅ connects between the TRICKLE BIAS terminal of batterycharger controller chip 451 and the collector (output) of passtransistor 455.

The PNP pass transistor 455 has its base connected to, and is thuscontrolled by, the DRIVER SINK terminal of battery charger controller451. Similarly, the P-channel MOSFET activating transistor 470 has itsgate connected to, and is thus controlled by, the output of differentialcomparator 425 (i.e., the output of output selector stage 410). When itsgate receives the turn-off signal from output selector stage 410 (i.e.,injection control unit 50 is operating in its non-idle mode), transistor470 disconnects its source and drain terminals, thus effectivelydisconnecting power supply 120 from charging circuit 450 and injectioncontrol unit 50. In this state, when the activating transistor 470 isturned off, the Schottky Barrier diodes 430 are forward biased, thusleaving the batteries 143 to power the injection control unit.Conversely, when its gate receives the turn-on signal (i.e., injectioncontrol unit 50 is operating in its idle mode), transistor 470 turns on,thus connecting power supply 120 to the charging circuit 450 and theinjection control unit 50. In this state, when the activating transistor470 is turned on, the Schottky Barrier diodes 430 are obviously reversedbiased.

In this context, the CBC system 100 has been designed to charge thebatteries 143 of injection control unit 50 and thus enable the operatorto use the injector system continuously without the burden of swappingbatteries. The CBC system achieves these goals through two modes ofcharging: a low current charging mode and a multi-state charging mode.Whether disconnected from the injection control unit 50 or connectedthereto while it operates in the idle mode, as long as battery pack 140is connected to the power supply 120, the battery charger controller 451will charge the batteries 143. The particular charging mode in which itoperates depends on the voltage of batteries 143, as typically measuredat the V_(Batt) terminal. The charger controller 451 will enter neithermode until output selector stage 410 has output the turn-on signal toactivating transistor 470, under the circumstances noted above, and thetransistor 470 has responded thereto by connecting the power supply 120to the charging circuit 450.

When the power supply 120 is disconnected from the battery pack 140,Schottky diode 469 prevents the batteries 143 from discharging throughthe charging circuit 450. For the preferred application of injectioncontrol unit 50, as shown in FIG. 6A, it is preferred that the resistorR₁₀ of resistor divider network 460 be connected to the POWER INDICATEterminal of chip 451 instead of ground. This will keep discharging inthis circumstance to an absolute minimum.

With DC power supplied to charging circuit 450 via transistor 470, theCBC system 100 functions in the low current charging mode only when thevoltage of the batteries 143 has dropped below a preselected minimum.More specifically, at its VOLTAGE SENSE terminal inter alia, the batterycharger controller 451 monitors the voltage at the V_(Batt) terminal viaresistor divider network 460. As is apparent from FIG. 6A, the values ofthe resistors R₄, R₈, R₉ and R₁₀ determine the value of this preselectedminimum. For the preferred application of injection control unit 50, thevalues of these resistors are preferably selected so that wheneverV_(Batt) drops below 10.8V the corresponding voltage at the VOLTAGESENSE terminal will compel the chip 451 to enter its low currentcharging mode of operation. In this mode, the battery charger controller451 does not activate (i.e., turns off) pass transistor 455 but insteadsupplies current from its TRICKLE BIAS terminal to the batteries 143(V_(Batt) terminal) via resistor R₅ and Schottky diode 469. The outputcurrent of the chip 451 is limited to this low or trickle level untilthe voltage of batteries 143 (V_(Batt) terminal) reaches the preselectedminimum level. Without this low current charging mode, the batterycharger controller 451 would otherwise charge the batteries 143 at ahigh current even if a battery cell was shorted.

The battery charger controller 451 continues trickle charging thebatteries 143 until they reach the preselected minimum of 10.8V, and inthe process prevents high current charging if a battery cell is shorted.The controller chip 451 uses the 10.8V level as the minimum voltagerequired for the CBC system 100 to begin functioning in the multi-statecharging mode.

The UC3906 controller chip 451 in its multi-state charging mode iscapable of charging the batteries 143 according to three separate chargestates: a high current bulk-charge state, a controlled over-chargestate, and a precision float-charge or standby state. As shown in FIG.7, the particular charge state in which chip 451 operates dependsvariously on the voltage of batteries 143 and the charging currentsupplied to the batteries via pass transistor 455, which chip 451controls by controlling the bias applied to the base of the passtransistor 455.

With reference to FIG. 7, once the voltage of the batteries 143 reachesor exceeds the preselected minimum (V_(T)) of 10.8V, the battery chargercontroller 451 will begin charging the batteries 143 according to thebulk-charge state (STATE 1). In this state, the controller chip 451 willsupply via pass transistor 455 a peak charge current (I_(MAX)) that isdetermined in part by sense resistor R₃, as disclosed in DatasheetSLUS186B (Rev. July 2003) cited above. For the preferred application ofinjection control unit 50, the value of sense resistor R₃ is preferablyselected so that the peak charge current is on the order of 750 mA. Thecontroller chip 451 continues charging the batteries 143 according tothe bulk-charge state until the battery voltage (V_(Batt)) reaches a setpercentage of an overcharge level (V_(OC)). For the preferredapplication of injection control unit 50, the set percentage and theovercharge level are preferably 95% and 14.7V, respectively. As with thepreselected minimum voltage, these values are determined by the valuesof the resistors in resistor divider network 460. Once the batteryvoltage reaches or exceeds 95% of 14.7V (i.e., V₁₂≈13.97V), the chargercontroller 451 transitions to the over-charge state (STATE 2). In thisstate, chip 451 continues charging the batteries 143 until the chargingcurrent falls to a minimum threshold (I_(OCT)≈75 mA), which isdetermined by chip 451 and sense resistor R₃. When the charging currentfalls below the minimum threshold, the controller chip 451 transitionsto the standby state (STATE 3). In this state, the chip applies to thebatteries a constant voltage, which is determined by appropriateselection of the resistors in network 460. The charging stage 440 willremain in the standby state until the battery voltage drops a specifiedpercentage below a float level (V_(F)) upon which the chip 451 willcommence operating according to the bulk-charge state. For the preferredapplication of injection control unit 50, the specified percentage andthe float level are preferably 10% and 13.5V, respectively. Thebulk-charge state thus preferably restarts when the battery voltagedrops to V₃₁≈12.15V. These values are also determined, at least in part,by resistors R₄, R₈, R₉ and R₁₀ of resistor divider network 460, asdisclosed in Datasheet SLUS186B.

Referring to the alphabetic designations in FIG. 7, the controller chip451 in its low current and multi-state charging modes operates assummarized below. At position A, the input power turns on, and thebattery charges at the trickle current rate. At position B, the batteryvoltage V_(Batt) reaches V_(T). This enables the driver chip 451 andturns off its trickle bias output, and allows the battery to charge atthe I_(MAX) rate. At position C, the transition voltage V₁₂ is reachedand the controller chip 451 now operates in the over-charge state. Atposition, D, the battery voltage approaches the over-charge level V_(OC)and the charge current begins to taper. At position E, the chargecurrent tapers to I_(OCT). The CURRENT SENSE output (CSOUT), preferablytied to the OC TERM terminal, goes high. The controller chip 451 thenchanges to the float state and holds the battery voltage V_(Batt) atV_(F). At position F, the injection control unit 50 begins to dischargethe battery 143 at a current greater than I_(MAX). At position G, theload discharges the battery such that the battery voltage V_(Batt) fallsbelow V₃₁. The controller chip 451 then again operates in thebulk-charge state (STATE 1).

The indicator stage 480 includes a comparator circuit 481 and anindicator 482. The comparator circuit 481 can be implemented with theLM2903MX differential comparator chip produced by FairchildSemiconductor Corporation. The indicator 482 can take the form of theKA-3528MBC surface mountable light-emitting diode (LED) chip produced byKingbright Corporation. Differential comparator 481 has its positiveinput connected to the 5V DC received from regulator 490 and itsnegative input connected to a resistor divider network, R₁₅ and R₁₇. Theoutput of comparator 481 is connected to the cathode of LED 482 viaresistor R₁₄, with the anode of LED 482 connected to power supply 120.

The resistor divider network of R₁₅ and R₁₇ steps down the 15V DCreceived from power supply 120. For the preferred application ofinjection control unit 50, it is preferred that the values of resistorsR₁₅ and R₁₇ be selected so that LED 482 will illuminate when the voltagefrom power supply 120 is greater than or equal to a preset upper levelof 14.4V. This is because that, for the preferred application, 14.4V isthe minimum voltage required to efficiently charge the batteries 143.Conversely, when the voltage from power supply 120 is less than a presetlower level of 13.8V, LED 482 will not illuminate. LED 482 may be on oroff in the transition region between 13.8 V and 14.4 V. The purpose ofindicator 482 is preferably to indicate to the operator that the powersupply 120 is operational and is delivering the required minimum voltageto the battery pack 140.

Having now described in detail the preferred implementation of eachstage of charger module 400, it should now be apparent that each stagecould alternatively be fashioned from different circuit components orother arrangements of circuit components. Such different components orother arrangements of components that together perform the same functionas any one of the cited stages are intended to be encompassed by thefollowing claims.

The CBC system 100 can be deployed in any one of at least twoconfigurations, namely, the scanner room configuration or the controlroom configuration. FIG. 8A shows the CBC system 100 deployed in the MRsuite according to the control room configuration. In thisconfiguration, the power supply 120 and its AC power cord 110 aresituated in the control room 2 of the MR suite, with the AC power cord110 plugged into an AC outlet. The DC power cord 130 from power supply120 is routed through the penetration panel 16 separating the controland scanner rooms, and eventually connects to the battery pack 140 inthe scanner room 1.

FIG. 8B shows a preferred approach for routing the DC power cord 130through the penetration panel 16. In this preferred manifestation, theDC power cord 130 includes a filtered cable section 130c routed into anaperture in penetration panel 16 and two shielded cable sections 130aand 130b connected thereto on opposite sides of the penetration panel16. The filtered cable section 130c preferably comprises a D-shellconnector 131 at one end and a circular connector 132 at the other end.As shown in FIG. 8C, if the penetration panel 16 has a 9-pin connectorhole available as an aperture, then filtered cable section 130c can haveits D-shell connector 131 inserted into the hole from the control roomside and connected with its corresponding mate on shielded cable section130b. Similarly, as shown in FIG. 8D, if the penetration panel 16 has acircular or similar hole available as an aperture, then filtered cablesection 130c can have its circular connector 132 inserted into the holefrom the scanner room side and connected with its corresponding mate onshielded cable section 130a. Ferrite clamps (not shown) are preferablyinstalled on both ends of cable section 130b. The cable section 130a inthe control room 2 connects the power supply 120 to the filtered cablesection 130c, and cable section 130b in the scanner room 1 connects thefiltered cable section 130c to battery pack 140. The battery pack 140then plugs into the socket 52 of injection control unit 50.

FIG. 9 shows the CBC system 100 deployed in the MR suite according tothe scanner room configuration. In this configuration, the AC power cord100, the power supply 120, the DC power cord 130 and the battery pack140 are all situated in the scanner room 1 of the MR suite. The powersupply 120 should be securely mounted to the floor or a wall at asufficient distance from the scanner to avoid causing artifacts in theimages. The AC power cord 110 is plugged into an AC outlet in thescanner room, preferably as far away as possible from the scanner. TheDC power cord 130 interconnects the power supply 120 and the batterypack 140, with the battery pack 140 plugged into the socket 52 ofinjection control unit 50. In this configuration, both of the powercords 110 and 120 are preferably shielded.

The CBC system 100 and its preferred application of injection controlunit 50, also referred to as a scanner room unit (SRU), are shown inFIG. 10 in block diagram form.

The presently preferred and alternative embodiments for carrying out theinvention have been set forth in detail according to the Patent Act.Persons of ordinary skill in the art to which this invention pertainsmay nevertheless recognize alternative ways of practicing the inventionwithout departing from the spirit of the following claims. Consequently,all changes and variations which fall within the literal meaning, andrange of equivalency, of the claims are to be embraced within theirscope. Persons of such skill will also recognize that the scope of theinvention is indicated by the following claims rather than by anyparticular example or embodiment discussed or illustrated in theforegoing description.

Accordingly, to promote the progress of science and useful arts, wesecure for ourselves by Letters Patent exclusive rights to all subjectmatter embraced by the following claims for the time prescribed by thePatent Act.

1. A battery charger system for an injector system, said injector systemhaving an idle mode of operation and a non-idle mode of operation, thebattery charger system comprising: (a) a first power cord for conveyingAC power from a source thereof; (b) an AC/DC converter for convertingthe AC power received from said first power cord to DC power; (c) asecond power cord for conveying the DC power received from an output ofsaid AC/DC converter; and (d) a battery pack including a battery and acharging module, said charging module for receiving the DC power fromsaid AC/DC converter via said second power cord and for monitoring theoperating mode of said injector system such that when said injectorsystem is operating in (I) said idle mode, said charger module providesthe DC power received from said AC/DC converter to said battery for thecharging thereof and (II) said non-idle mode, said charger moduleprevents the DC power from said AC/DC converter from reaching saidbattery and thus enables said battery to provide DC power to saidinjector system.
 2. The battery charger system of claim 1 wherein saidcharger module also provides the DC power received from said AC/DCconverter to said injector system when said injector system is operatingis said idle mode of operation.
 3. The battery charger system of claim 1wherein said charger module also enables the DC power from said AC/DCconverter to charge said battery when said battery pack is disconnectedfrom said injector system.
 4. The battery charger system of claim 1wherein, when said AC/DC converter is disconnected from said batterypack, said charging module enables said battery to provide DC power tosaid injector system whether said injector system is operating in saidnon-idle mode or said idle mode.
 5. The battery charger system of claim1 wherein said second power cord comprises: (a) a central section forrouting into an aperture of a penetration panel; (b) a first end sectionon a first side of the penetration panel for interconnecting saidcentral section and said AC/DC converter; and (c) a second end sectionon a second side of the penetration panel for interconnecting saidcentral section and said battery pack.
 6. The battery charger system ofclaim 5 wherein said central section comprises: (a) a circular connectorat one end thereof for connection to said first end section; and (b) aD-shell connector at another end thereof routed into said aperture forconnection to said second end section.
 7. The battery charger system ofclaim 5 wherein said central section comprises: (a) a D-shell connectorat one end thereof for connection to said second end section; and (b) acircular connector at another end thereof routed into said aperture forconnection to said first end section.
 8. The battery charger system ofclaim 5 further comprising ferrite clamps installed on both ends of saidsecond end section.
 9. A battery charger system for use with aninjection control unit of an injector system, the battery charger systemcomprising: (a) an AC/DC converter for converting AC power from a sourcethereof to DC power; and (b) a battery pack including a battery and acharging module, said charging module for monitoring an operating modeof said injector system such that when said battery pack is: (I)disconnected from said injection control unit, said charging moduleenables said AC/DC converter to charge said battery with the DC powertherefrom; and (II) connected to said injection control unit, (A) upondetecting said injector system in an idle mode of operation, saidcharger module routes the DC power from said AC/DC converter to bothsaid battery for the charging thereof and said injection control unitfor operation thereof; and (B) upon detecting said injector system in anon-idle mode of operation, said charger module prevents said AC/DCconverter from charging said battery and enables said battery to provideDC power to said injection control unit.
 10. The battery charger systemof claim 9 wherein, when said AC/DC converter is disconnected from saidbattery pack, said charging module enables said battery to provide DCpower to said injection control unit whether said injector system isoperating in said non-idle mode or said idle mode.
 11. The batterycharger system of claim 9 further including a DC power cord forinterconnecting said AC/DC converter and said battery pack on oppositessides of a penetration panel, said DC power cord comprising: (a) acentral section for routing into an aperture of the penetration panel;(b) a first end section on a first side of the penetration panel forinterconnecting said central section and said AC/DC converter; and (c) asecond end section on a second side of the penetration panel forinterconnecting said central section and said battery pack.
 12. Thebattery charger system of claim 11 wherein said central sectioncomprises: (a) a circular connector at one end thereof for connection tosaid first end section; and (b) a D-shell connector at another endthereof routed into said aperture for connection to said second endsection.
 13. The battery charger system of claim 11 wherein said centralsection comprises: (a) a D-shell connector at one end thereof forconnection to said second end section; and (b) a circular connector atanother end thereof routed into said aperture for connection to saidfirst end section.
 14. The battery charger system of claim 11 furthercomprising ferrite clamps installed on both ends of said second endsection.
 15. A battery charger system for use with a battery-poweredsystem, the battery charger system comprising: (a) a power supply forsupplying DC power; and (b) (a) a battery pack including a battery and acharging module, said charging module connectible to, said battery packadapted for plugging into said battery-powered system and beingconnectible to a power supply for receiving the DC power therefrom; andcapable of (b) a charging module for monitoring an operating mode ofsaid battery-powered system when linked thereto such that when saidbattery pack is: (I) disconnected from said battery-powered system, saidcharging module enables battery is capable of being charged by saidpower supply to charge said battery with the DC power received therefromwhen said power supply is connected to said battery pack; and (II)connected to plugged into said battery-powered system, (A) upondetecting said battery-powered system in an idle mode of operation, saidcharger module routes the DC power from said power supply to both saidbattery for the charging thereof and said battery-powered system foroperation thereof; and (B) upon detecting said battery-powered system ina non-idle mode of operation, said charger module prevents said powersupply from charging said battery and enables said battery to provide DCpower to said battery-powered system; wherein said charging moduleincludes an output selector stage and a charging stage such that: (III)said output selector stage senses current drawn by said battery-poweredsystem and provides a turn-on signal when said current is less than apredetermined level and a turn-off signal when said current is greaterthan said predetermined level; and (IV) said charging stage is connectedto said output selector stage such that upon receiving (A) said turn-offsignal, said charging stage prevents said battery from being charged bysaid power supply and enables said battery to provide DC power to saidbattery-powered system and (B) said turn-on signal, said charging stageenables DC power from said power supply to be conveyed to saidbattery-powered system and assumes: (i) a low current charging mode,when a voltage level of said battery is less than a preselected minimumlevel, wherein said charging stage charges said battery with a chargingcurrent therefor limited to a trickle level, and (ii) a multi-statecharging mode, when said voltage level of said battery is saidpreselected minimum level or greater, wherein said charging stageoperates according to: (a) a bulk-charge state, when said voltage levelof said battery is said preselected minimum level or greater yet below aset percentage of an overcharge level, wherein said charging stagecharges said battery with said charging current at a peak level thereof,(b) an over-charge state, when said voltage level of said battery isequal to or exceeds said set percentage of said overcharge level,wherein said charging stage continues charging said battery until saidcharging current falls to a minimum threshold, and (c) a standby state,when said charging current falls below said minimum threshold, whereinsaid charging stage applies a constant voltage to said battery untilsaid voltage level of said battery drops at least a specified percentagebelow a float level upon which said charging stage will commenceoperating according to said bulk-charge state.
 16. The battery chargersystem of claim 15 wherein, when said battery pack is connected to saidbattery-powered system and said power supply is disconnected from saidbattery pack, said charging module enables said battery to provide DCpower to said battery-powered system whether said battery-powered systemis operating in said non-idle mode or said idle mode.
 17. The batterycharger system of claim 15 wherein said battery-powered system is aninjector system.
 18. The battery charger system of claim 15 furtherincluding a DC power cord for interconnecting said power supply and saidbattery pack on opposite sides of a barrier, said DC power cordcomprising: (a) a central section for routing into an aperture of thebarrier; (b) a first end section on a first side of the barrier forinterconnecting said central section and said power supply; and (c) asecond end section on a second side of the barrier for interconnectingsaid central section and said battery pack.
 19. The battery chargersystem of claim 18 wherein said central section comprises: (a) acircular connector at one end thereof for connection to said first endsection; and (b) a D-shell connector at another end thereof routed intosaid aperture for connection to said second end section.
 20. The batterycharger system of claim 18 wherein said central section comprises: (a) aD-shell connector at one end thereof for connection to said second endsection; and (b) a circular connector at another end thereof routed intosaid aperture for connection to said first end section.
 21. The batterycharger system of claim 18 further comprising ferrite clamps installedon both ends of said second end section.
 22. A charging module for abattery for use with an injection control unit of an injector system,the charging module comprising: (a) an output selector stage for sensinga mode of operation of said injection control unit and for providing aturn-on signal when said injection control unit is operating in an idlemode and a turn-off signal when said injection control unit is operatingin a non-idle mode; (b) a charging stage connected to said outputselector stage such that upon receiving (I) said turn-off signal, saidcharging stage prevents said battery from being charged by a powersupply therefor and enables said battery to provide DC power to saidinjection control unit and (II) said turn-on signal, said charging stageenables DC power from said power supply to be conveyed to said injectioncontrol unit and assumes: (A) a low current charging mode, when avoltage level of said battery is less than a preselected minimum level,wherein said charging stage charges said battery with a charging currenttherefor limited to a trickle level, and (B) a multi-state chargingmode, when said voltage level of said battery is said preselectedminimum level or greater, wherein said charging stage operates accordingto: (i) a bulk-charge state, when said voltage level of said battery issaid preselected minimum level or greater yet below a set percentage ofan over-charge level, wherein said charging stage charges said batterywith said charging current at a peak level thereof, (ii) an over-chargestate, when said voltage level of said battery is equal to or exceedssaid set percentage of said overcharge level, wherein said chargingstage continues charging said battery until said charging current fallsto a minimum threshold, and (iii) a standby state, when said chargingcurrent falls below said minimum threshold, wherein said charging stageapplies a constant voltage to said battery until said voltage level ofsaid battery drops at least a specified percentage below a float levelupon which said charging stage will commence operating according to saidbulk-charge state; and (c) an indicator stage for indicating when saidpower supply is capable of providing to the charging module sufficientpower to efficiently charge said battery.
 23. The charging module ofclaim 22 wherein said output selector stage includes: (a) a currentmonitoring circuit for sensing current drawn by said injection controlunit and for outputting an output voltage (I) less than a predeterminedthreshold when said current is less than a predetermined level therebyindicating that said injection control unit is operating in said idlemode and (II) greater than said predetermined threshold when saidcurrent is greater than said predetermined level thereby indicating thatsaid injection control unit is operating in said non-idle mode; and (b)a comparator circuit for comparing said output voltage of said currentmonitoring circuit with a nominal reference voltage such that when saidoutput voltage is (I) less than said predetermined threshold, saidcomparator circuit outputs said turn-on signal and (II) greater thansaid predetermined threshold, said comparator circuit outputs saidturn-off signal.
 24. The charging module of claim 23 wherein saidcurrent monitoring circuit includes: (a) a current shunt monitor formonitoring said current drawn by said injection control unit andoutputting an interim current proportional thereto; and (b) an externalload resistor for converting said interim current into said outputvoltage corresponding thereto.
 25. The charging module of claim 22wherein said charging stage includes an activating transistor and acharging circuit such that: (a) said activating transistor is connectedto said output selector stage so that upon receiving (I) said turn-onsignal, said activating transistor operably connects said power supplyto said charging circuit and (II) said turn-off signal, said activatingtransistor operably disconnects said power supply from said chargingcircuit; and (b) said charging circuit is responsive to (I) saidturn-off signal by preventing said battery from being charged by saidpower supply and enabling said battery to provide DC power to saidinjection control unit and (II) said turn-on signal by being operablevariously in said low current charging mode and said multi-statecharging mode depending on said voltage level of said battery.
 26. Thecharging module of claim 25 wherein said charging circuit includes aUnitrode UC3906 battery charger controller chip.
 27. The charging moduleof claim 25 wherein said activating transistor is a P-channel MOSFET.28. The charging module of claim 25 wherein said indicator stageincludes: (a) a light-emitting diode having an anode connected to saidpower supply; and (b) a comparator circuit having an output connected toa cathode of said light-emitting diode, said comparator circuit forcomparing an output voltage of said power supply with a referencevoltage such that when said output voltage is (I) greater than a presetupper level, said comparator circuit turns on said light-emitting diodeand (II) less than a preset lower level, said comparator circuit turnsoff said light-emitting diode.
 29. A charging module for a battery foruse with a battery-powered system, the charging module comprising: (a)an output selector stage for sensing current drawn by saidbattery-powered system and for providing a turn-on signal when saidcurrent is less than a predetermined level and a turn-off signal whensaid current is greater than said predetermined level; and (b) acharging stage connected to said output selector stage such that uponreceiving (I) said turn-off signal, said charging stage prevents saidbattery from being charged by a power supply therefor and enables saidbattery to provide DC power to said battery-powered system and (II) saidturn-on signal, said charging stage enables DC power from said powersupply to be conveyed to said battery-powered system and assumes: (A) alow current charging mode, when a voltage level of said battery is lessthan a preselected minimum level, wherein said charging stage chargessaid battery with a charging current therefor limited to a tricklelevel, and (B) a multi-state charging mode, when said voltage level ofsaid battery is said preselected minimum level or greater, wherein saidcharging stage operates according to: (i) a bulk-charge state, when saidvoltage level of said battery is said preselected minimum level orgreater yet below a set percentage of an over-charge level, wherein saidcharging stage charges said battery with said charging current at a peaklevel thereof, (ii) an over-charge state, when said voltage level ofsaid battery is equal to or exceeds said set percentage of saidovercharge level, wherein said charging stage continues charging saidbattery until said charging current falls to a minimum threshold, and(iii) a standby state, when said charging current falls below saidminimum threshold, wherein said charging stage applies a constantvoltage to said battery until said voltage level of said battery dropsat least a specified percentage below a float level upon which saidcharging stage will commence operating according to said bulk-chargestate.
 30. The charging module of claim 29 further comprising anindicator stage for indicating when said power supply is capable ofproviding to the charging module sufficient power to efficiently chargesaid battery.